Lupinus arboreus
| Lupinus arboreus | |
| Light: |  |
| Moisture: |   |
| Hardiness: | 8 |
| Soil pH: | 5.6-8.4 |
| Evergreen | |
| Height: | 5' |
| Width: | 4' |
| Speed: | Fast |
| Blooms: | Late Spring-Late Summer |
| Native to: | |
| Nitrogen Fixer | |
| Tea: | Yes |
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Lupinus arboreus (common name: tree lupin)
Propagation: Pre-soak the seed for 24 hours in warm water and then sow in early spring in a greenhouse[1][2]. Germination should take place within a couple of weeks. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in early summer.
It should also be possible to sow the seed in situ in mid to late spring. Protect the seed from mice.
Cuttings of short side-shoots with a heel, July/August in a frame[3].
Cultivation: Requires a well-drained dry or moist soil in a sunny position[3][4]. Prefers an alkaline soil[5]. Grows well near the coast[3], resisting maritime exposure. Established plants are drought tolerant[6]. Plants can be grown in quite coarse grass, which can be cut annually in the autumn[7].
Hardy to about -15°c[8][2]. Plants are hardy in all but severe winters in Britain[2], though they become less hardy with age[3].
A fast-growing but short-lived plant[4], especially when growing in rich soils[3]. Plants have reached 2.7 metres tall and wide within 4 years from seed in a rich soil, flowering and producing seed prolifically[3]. Plants self-sow when in a suitable position[2].
The flowers bear the fragrance of white clover[9].
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[2].
Range: South-western N. America - California to Oregon. Naturalized in S. England.
Habitat: Stable sand dunes, coastal scrub and pine forest close to the coast. Naturalized by the sea in S. England[8].
Usage: A bright yellow dye is obtained from the flowers[10].
The root fibres have been used to make a string for making nets etc[11].
Plants are used in land reclamation schemes to stabilize sandy soils and dunes[2]. Because they are fast growing and tolerant of maritime exposure, they quickly provide shelter for other plants as well as enriching the soil with nitrogen[K].
An excellent pioneering plant in permaculture, even in exposed areas it grows rapidly to its maximum height of about 1.5 metres and will give shelter to enable other less tolerant plants to become established. It is especially useful for helping the establishment of shrubs and herbaceous perennials in small gardens[K].
Pollinators: Bees
Soil: Can grow in light and medium soils.
Drainage: Prefers well drained soil.
Wind: Tolerates maritime wind exposure
In Leaf: Evergreen
Flower Type: Hermaphrodite
Known Hazards: The seed of many lupin species contain bitter-tasting toxic alkaloids, though there are often sweet varieties within that species that are completely wholesome[12][13]. Taste is a very clear indicator. These toxic alkaloids can be leeched out of the seed
Links
References
- ↑ Chittendon, Fred. RHS Dictionary of Plants. Oxford University Press, 1951.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Huxley, Anthony. The New Royal Horticultural Society Dictionary of Gardening. MacMillan Press, 1992.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Bean, William. Trees and Shrubs Hardy in Great Britain. Murray, 1981.
- ↑ 4.0 4.1 Thomas, Graham. Ornamental Shrubs, Climbers and Bamboos. Murray, 1992.
- ↑ Brickell, Christopher. The RHS Gardener's Encyclopedia of Plants and Flowers. Dorling Kindersley Publishers, 1990.
- ↑ Chatto, Beth. The Damp Garden. Dent, 1982.
- ↑ Thomas, Graham. Perennial Garden Plants. J. M. Dent & Sons, 1990.
- ↑ 8.0 8.1 Phillips, Roger and Martyn Rix. Shrubs. Pan Books, 1989.
- ↑ Genders, Roy. Scented Flora of the World. Robert Hale, 1994.
- ↑ Grae, Ida. Nature's Colors. MacMillan Publishing, 1974.
- ↑ Moerman, Daniel. Native American Ethnobotany. Timber Press, 1998.
- ↑ Frohne, Dietrich and Hans Pfänder. J. A Colour Atlas of Poisonous Plants. Timber Press, 1984.
- ↑ Cooper, Marion. Poisonous Plants in Britain and their Effects on Animals and Man. The Stationery Office, 1984.